If you don't need to preserve backward compatibility with mod_cgi, you can port mod_cgi scripts to use mod_perl-specific APIs. This allows you to benefit from features not available under mod_cgi and gives you better performance for the features available under both. We have already seen how easily Apache::Registry turns scripts into handlers before they get executed. The transition to handlers is straightforward in most cases.
Let's see a transition example. We will start with a mod_cgi-compatible script running under Apache::Registry, transpose it into a Perl content handler without using any mod_perl-specific modules, and then convert it to use the Apache::Request and Apache::Cookie modules that are available only in the mod_perl environment.